The present invention generally relates to an exterior sideview mirror assembly suitable for mounting on a vehicle and, more particularly, to an exterior sideview mirror assembly which incorporates a film appliquxc3xa9 to provide a decorative appearance to the assembly.
More recently, the trend in exterior sideview mirror assemblies has been to provide housings for the exterior sideview mirror assemblies that match the body of the vehicle. In addition, these housings are often molded with their respective mounting arms or xe2x80x9csailsxe2x80x9d to provide a unitary housing which exhibits enhanced aerodynamic characteristics. However, in an attempt to reduce the cost of manufacturing such assemblies, a composite assembly has been developed which includes a base housing or frame and a shell or skull cap which is mounted to the frame, for example by snap connectors. The frame is formed from an engineering plastic, typically reinforced engineering plastic, such as reinforced nylon or the like. The shell or skull cap is formed from a plastic substrate which is then painted to match the vehicle body color. The structural capacity of the housing is provided by the frame, with the shell providing a decorative covering over at least a portion of the frame so that the housing generally matches the vehicle body. In some cases, however, these sideview mirror assemblies have exhibited increased wind noise. This wind noise is generated, such as, by the gap between the decorative shell and the frame of the mirror assembly.
Various attempts have been made to minimize and/or eliminate the wind noise. One approach is to eliminate the gap between the decorative shell and the frame. However, in order to eliminate this gap, the tolerances on the respective parts must be extremely tight which adds to the expense of the sideview mirror assembly, thus effectively eliminating the savings achieved by the skull cap design. Another approach is to alter the surface topology of the decorative shell to separate the air flow over the exterior sideview mirror assembly, which reduces the noise of the wind flow.
For example, in German Pat. No. 4,039,484 to Bayerische Motoren Werke AG, a plurality of raised portions or xe2x80x9cbumpsxe2x80x9d are provided to separate the air flow over the housing. However, these raised portions are not aesthetically pleasing to some automobile manufactures and, further, project above the assembly potentially creating a distraction to the driver. In addition, it has been found that when a discontinuity is introduced into the substrate of the skull cap (such as when it is molded into a molding tool), that the noise reduction advantages of the surface molded discontinuity is significantly reduced by the painting process since the painting process alters the surface topology of the substrate. Rather than following the surface discontinuities, the paint partially fills in the discontinuities.
More recently in copending U.S. patent application Ser. No. 09/482,199, entitled OUTSIDE SIDEVIEW MIRROR ASSEMBLY WITH REDUCED WIND NOISE, filed Jan. 12, 2000, by Leo W. Pavao and Tun-Jen Chu, commonly assigned to Donnelly Corporation, which is herein incorporated reference in its entirety, a skull cap incorporating wind noise reduction features is disclosed that uses a film to provide the desired decorative appearance but which maintains the definition of the wind noise reduction features of the skull cap so that the noise reduction features are maintained even after the skull cap is decorated.
While these decorative covers offer unique styling and assembly and, further, have resolved the wind noise problems associated with conventional skull caps, these decorative covers still increase the number of parts and hence the assembly time as compared to conventional unitary sideview mirror designs. Consequently, there is a need for an exterior sideview mirror assembly which includes a unique outer surface for matching the vehicle to which the assembly is to be mounted to provide an aesthetic appearance of the mirror assembly without the noise associated with conventional skull cap designs while reducing the number of parts.
The present invention provides an exterior sideview mirror assembly which incorporates a film appliquxc3xa9 that preferably matches the color of the vehicle body to provide a decorative appearance to the mirror assembly. The film appliquxc3xa9 is molded with the housing substrate and as a result eliminates the gap associated with conventional skull cap designs.
According to one form of the invention, a method of forming a mirror housing includes providing a molding apparatus having a mold cavity, placing a film appliquxc3xa9 in the mold cavity, and injecting a polymer into the mold cavity over at least a portion of a side of the film appliquxc3xa9 to form a housing wall of the mirror housing wherein the film adheres to the substrate forming the housing wall.
In further aspects, the mold apparatus comprises an injection molding apparatus which injects a heated polymer into the mold cavity.
In other aspects, the film appliquxc3xa9 is restrained in the mold cavity when the polymer is injected into the mold cavity. For example, the mold cavity may be configured to restrain the film appliquxc3xa9 in the mold cavity, including by forming a projection on a side of the mold cavity. The projection assists in holding to film appliquxc3xa9 in the mold cavity. In other aspects, the film is held in place by a vacuum. In yet another aspect, a primer is provided on at least the portion of the film appliquxc3xa9 to increase the adhesion of the film appliquxc3xa9 to the substrate forming the housing wall.
In another form of the invention, a vehicular exterior sideview mirror assembly includes a mirror housing which is adapted for mounting to a vehicle. The mirror housing is formed by molding and has a housing wall that defines a cavity and an opening for facing rearward of the vehicle when the mirror assembly is mounted to the vehicle. A reflective element is provided in the cavity for rearward viewing of the vehicle. In addition, the mirror housing has a forward facing side when the mirror assembly is mounted to the vehicle, with at least a portion of the forward facing side including a decorative film appliquxc3xa9 molded therewith to provide a decorative function for the mirror assembly.
In one aspect, the film appliquxc3xa9 comprises a film laminate. For example, the film laminate may include at least one backing sheet and at least one coating over the backing sheet. The coating preferably has a color either for matching the vehicle body paint, for providing an accent color, or for providing a metallic appearance. In further aspects, the film laminate has a thickness in a range of about 10 to 60 mils, more preferably, in a range of about 12 to 35 mils and, most preferably, in a range of about 15 to 30 mils.
In other aspects, the housing includes a styling feature which visually distinguishes the film appliquxc3xa9 from the housing wall to simulate a removable skull cap mirror design. In further aspects, the housing of the exterior mirror assembly comprises a polymer resin, for example a filled polymer resin, including a filled polypropylene.
According to another form of the invention, a vehicular sideview exterior mirror assembly includes a reflective element and a mirror housing which is adapted to mount to a vehicle. The mirror housing includes a mirror casing having a casing wall which defines a cavity and an opening for facing rearward of the vehicle when the vehicular sideview exterior mirror assembly is mounted to the vehicle. The mirror assembly further includes a reflective element in the cavity for rearward viewing of the vehicle when the vehicular sideview exterior mirror assembly is mounted to the vehicle. The mirror casing wall has at least a portion thereof decorated with a film appliquxc3xa9 , which is molded on the portion of the mirror casing wall and provides a decorative function to the vehicular sideview exterior rearview mirror assembly. For example, the film appliquxc3xa9 may be molded with the portion by injection molding.
In other aspects, the mirror casing wall includes a styling feature that visually distinguishes the film appliquxc3xa9 from the casing wall to simulate a removable skull cap mirror assembly design.
In yet other aspects, the film appliquxc3xa9 comprises a film laminate and includes at least one backing sheet and at least one coating over the backing sheet. The coating has a color which either generally matches the vehicle body paint, includes an accent color, or provides a metallic appearance.
In another form of the invention, a molding apparatus for forming a mirror housing for a vehicle mirror assembly includes a first mold plate having a first facing surface and a second mold plate having a second facing surface. The first and second facing surfaces define therebetween a mold cavity. The first mold plate is adapted to hold a film appliquxc3xa9 therein, with the second mold plate having at least one injection port through which a polymer is injected into the mold cavity for forming a housing wall of the mirror housing along with the film appliquxc3xa9 positioned in the cavity.
In other aspects, the first side of the mold cavity includes a projection to assist holding the film appliquxc3xa9 in the mold cavity. For example, the projection may comprise a peripheral ridge, which encircles the film appliquxc3xa9 .
It can be appreciated from the foregoing that a unitary or one piece mirror housing is provided or formed that offers the same styling features as a painted unitary molded mirror housing or a conventional skull cap design but without the associated expense. These and other features, purposes and advantages will be appreciated more fully when the drawings are viewed in conjunction with the detailed description which follows.